J. Heinonen et P. Koskela, A-INFINITY-CONDITION FOR THE JACOBIAN OF A QUASI-CONFORMAL MAPPING, Proceedings of the American Mathematical Society, 120(2), 1994, pp. 535-543
We show that the Jacobian J(f) of a quasi-conformal mapping f:B(n) -->
D is an A(infinity)-weight in B(n) if and only if D is a John domain.
A similar question concerning J(f-1) is also studied.